Answer: C .
and 
Step-by-step explanation:
Definition:
Null hypothesis
is a statement about the population parameter according to the objective raised by the researcher . It contains '=' , '≤' and '≥' signs.
Alternative hypothesis
is also a statement about the population parameter but against null hypothesis . It contains '≠' , '<' and '>' signs.
Let
be the average customer waiting time for the population.
Given : The average customer waiting time at a fast food restaurant has been 7.5 minutes.
Objective of test : After using new system , the average customer waiting time is at least 7.5 or less than 7.5.
Then, the null and alternative hypothesis for this scenario will be :


X+1=y+1
X-Y= 0
Hope this helped you
Answer: Equation: 4
-2
; estimate: a
little more than 2 inches; answer: 2 
inches.
Step-by-step explanation:
58 103 72
47 13 71
Hope I helped!
~ Zoe